The present invention generally relates to reflectors that are used for highway traffic markers, delineators and safety devices and, more particularly, to illuminated reflectors having a photovoltaic power source.
Reflectors for highway traffic markers, delineators, and other safety devices may be color coded and illuminated reflectors may be used to delineate highway traffic lanes, roadway edges, intersections, pedestrian crossings, pillars, posts, barricades, support columns, entry and exit ramps, and the location of fire hydrants. Illuminated reflectors may be used as safety devices such as on guard rails and crash cushion barriers. The illuminated reflector may be installed on the road at intersections indicating the presence of a "Stop" sign.
In addition to its use as a highway traffic marker and safety device, illuminated reflectors may be used in residential, industrial, institutional, and marine applications, such as in: marking steps or the presence of stairways in homes, hospitals, schools, plants, and offices; indicating safe walkways in plants and laboratories; marking marine buoy and pier locations; and marking entrance and exit paths, driveways, and parking locations. Illuminated reflectors may be used to mark locations of buried cable, water and gas pipelines, fire fighting hoses and water control valves, industrial control valves and other related applications.
U.S. Pat. No. 3,332,327, issued July 25, 1967, discloses a roadway traffic marker that includes a cube-corner reflex reflective optical system in which the cube axes of the cube-corner reflective elements are inclined so as to be substantially coincidental with the nominal incoming refracted ray. Additionally, that disclosed pavement marker includes a front face inclined at a predetermined angle to the roadway surface allowing the front face to be wiped clean by contact with vehicle tires.
Examples of other pavement markers are disclosed in U.S. Pat. Nos. 4,232,979, issued Nov. 11, 1980 and U.S. Pat. No. 4,340,319, issued July 20, 1982.
A problem with such highway markers and reflectors is that they are passive devices that provide roadway markings visible from oncoming traffic solely as a result of their ability to reflect light. It is highly desirable to provide a reflector that includes a light source so that the highway traffic reflectors and delineators are clearly visible and are visible over an extended distance beyond the range of a vehicle's headlamps by a driver of the vehicle. Additionally, it is highly desirable to provide an illuminated highway traffic reflector that includes a photovoltaic power system for charging a battery and extending the maintenance-free life performance of the traffic marker and that provides fail-safe operation.